I remember that long torque indicator capillary - we were threatened with death during an engine change if anything happened to it - had to be carefully stowed during removal and installation of engine - fortunately, never had to change one. Always wondered why they didn't have a torque transmitter on engine instead of that setup.
Had a peculiar one too on an Aeronaves de Mexico 302 where ammeter was fluctuating back and forth (high amp readings too) even with power off - even with the 28V and 112V battery sets disconnected. Finally found the lav was leaking fluid down on the ammeter shunt located behind stbd wall of fwd bag pit. Ammeter was reading current generated by corrosion of the shunt and connections.